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Y S I
Environmental
YSI 550A
1. Remove probe guard.
2.
IMPORTANT:
Thoroughly dry the
sensor so that no water enters the
probe port when the sensor is
removed.
3. Insert the long end of the hex key
wrench into the small hole in the side
of the DO sensor. Turn the wrench
counter clockwise until the sensor is
released.
4. Pull the DO sensor out of the probe.
The DO sensor is keyed, or has a flat
side, so that it can not be removed or
inserted improperly.
5. Make sure that the inside of the connector and the o-ring of the sensor are clean and dry, with no
contaminants, such as grease, dirt, or hair. Insert the new sensor.
6. Use the hex key wrench to tighten the screw, making sure that the screw does not stick out on either
side of the DO sensor module. Also, if the hex screw was removed completely, make sure that it is
not cross-threaded when replaced.
7. The YSI 559 DO module is shipped with a dry, protective membrane. Before using for the first
time, remove the protective cap and replace it with a new one following the instructions for
Membrane Cap Installation
.
ACCESSORIES/REPLACEMENT PARTS
The following parts and accessories are available from YSI or any YSI Authorized Dealer.
YSI Model Number
Description
5908
Membrane Kit, 1.25 mil PE, 6 caps and bottle of electrolyte solution
559
Replaceable DO Module
5238
Probe Reconditioning Kit, 10 sanding discs (400 grit) and sanding tool
5065
Form-Fitted Cover with Shoulder Strap
614
Ultra Clamp, C-Clamp Mount
4654 Tripod
5085
Hands Free Harness
5050
Small, Hard-sided Carrying Case, Foam-lined
5060
Small, Soft-sided Carrying Case, Precut Foam Interior
5080
Small, Hard-sided, Pelican Carrying Case, Precut Foam Interior
PROBE
GUARD
DO
SENSOR
CABLE
SET
SCREW
HEX KEY
WRENCH
